The present invention relates to a system for handling a volatile liquid used in a manufacturing process and more particularly relates to a system for handling a catalyst used in a foundry core making process.
The cold box core making process uses a liquid catalyst, such as dimethylethylamine (DMEA) or triethylamine (TEA), to cure cores during the production cycle. Specifically, resin coated sand is blown into a core box to form the desired shape. The liquid catalyst is pumped from a drum, typically of a forty-five or fifty-five gallon size, or a storage tank to each core machine where it is vaporized in a gassing station. The gas is then forced through the core by pressure so as to cure the resins coating the sand and thereby rigidify the core.
The catalysts commonly used are highly volatile and flammable and heretofore the known systems for supplying catalysts to core machines have not adequately addressed problems which result because of the characteristics of the catalysts.
Specifically, during the summer months temperatures often rise above the boiling point of the catalyst resulting in the catalyst vaporizing which causes the catalyst supply pump to become vapor locked Once this has happened, the pumping system has to be cooled before liquid can be pumped again. These delays in the production of molds can, especially in this era of just-in-time manufacturing procedures, result in delays in the production of machinery embodying the parts to be molded and hence can be quite costly.
In core making systems where the drums in which the catalyst is supplied is also used as the storage container from which the catalyst is pumped, the storage drums have to be changed before they are fully emptied of catalyst in order to avoid production delays Heretofore, the practice as been to keep these almost empty drums in storage until enough are on hand to make a full drum and then to manually pump the catalyst from the saved drums into a single drum. Unless properly stored, the almost empty drums represent a serious fire hazard. And even after this hand-pumping operation, sufficient residual catalyst is left in the drums that the drums cannot be sold or otherwise disposed of unless the residual catalyst is first flashed off by removing the drums from their storage area and transporting them to a special flash off cabinet. The transporting of these drums to the flash off cabinet is a dangerous operation because of the fire hazard involved.
The manual handling of the catalyst drums presents further hazards to those handling the drums since breathing of small amounts of vapors or contact with the catalyst can cause serious physical harm.